The present invention relates generally, as indicated, to a strip shearing and joining method and apparatus.
When welding or otherwise joining the leading end of one metal, plastic, coated metal or other strip or sheet with the trailing end of another preferably similar strip or sheet, it is desirable that the respective end edges be relatively fixedly positioned in proximity or in abutment with each other and in alignment with the joining tool, such as an electric arc welder, or the like. It is also desirable, especially when the ends of two strips are to be welded, that the ends are freshly sheared for cleanliness and for accurate parallel alignment of the same at the welding station.
One example of a mechanism for accurately spacing and positioning the ends of metal strips to be joined may be found in U.S. Pat. No. 3,239,909. In another device disclosed in U.S. Pat. No. 3,403,833 a combination slitter and welder is positioned over a fluid operated clamping arrangement, which includes two independent actuated clamps, at least one being laterally movable with its clamped strip end to a preferred position with respect to the other clamped strip end for welding of the two ends. The prior art strip shearing, clamping and joining devices employ relatively expensive, heavy and bulky hydraulic or pneumatic operating and control equipment, usually including hydraulic cylinders, lines, reservoirs, pumps and the like, which add to the cost, complexity and size of the equipment. The prior art hydraulically operated mechanisms also generally use a lower clamp bar that is relatively fixed on a frame bed over which the sheet or strip material may pass and an upper movable clamp bar located above the fixed lower clamp bar and movable toward the latter to clamp a strip therebetween, and to obtain such movement of the upper clamp bar suitable support and mounting structure therefor is required, which further adds to the expense, weight and bulkiness of the equipment.